The typical soft shell jacket is okay around town, but too single purpose and heavy for backpacking. I like soft shell pants for shoulder and winter seasons. If you know the conditions for the day, you might use a soft shell jacket on a day hike or for skiing, etc. The pants work more universally for me. If it gets colder, they layer up well with long johns.
There are so many variations on what could be called "soft shell," from lighter stretch knit type fabrics on out to stuff that is like body armor. I like the lighter stuff for pants.
One thing I have noticed with my pants is that they reach a certain point of water repellency and then you are WET. That mostly means being too lazy to stop and switch to rain pants when it is raining hard vs a drizzle. They have some DWR, but aren't a sub for rain gear. I haven't tried any with a membrane— sounds hot, heavy and expensive to me.
Hard fleece? Like smooth faced fleece? Some are more wind proof, and the smooth face might make sliding between layers easier. There are some that have a hard face and long fleeece inside. I've assumed the hard face was just a cheap way to finish the fabric, like the military "bear" jackets. I have an R4 jacket that has a close cropped outer fleece and a membrane, so it is wind proof, but too hot for exertion. It is just another variant of shift shell —- great for grocery shopping on a cold wet day.
I like a good fluffy 200w fleece for a mid layer, and especially vests. They meld well with wind shirt or rain shell and breath so much better than a hard shelled, thin loft insulated garment.